Research On The High Temperature Storage Performance Of Two Lithium Primary Battery And Life Prediction

The lithium primary battery whose anode is metal lithium, such as lithiummanganese batteries, lithium sulfur dioxide batteries, lithium thionyl chloride batteries,has properties of high specific energy, high capacity and high reliability etc, has beenused as portable electrical and electronic devices and has been widely used in the fieldof the national economy. Since the lithium primary batteries inevitably need to storea period of time during the process of actual use, especially when the batteries werestored under the condition of high temperature, the battery performances such asdischarge capacity, impedance and the safety performance would decrease with acertain degree, what′s more, the decrease would affect the use effect of the lithiumprimary batteries in different degrees. In order to further study the storageperformances of the lithium primary batteries, this article based on two kinds oflithium primary batteries, lithium thionyl chloride battery and lithium fluoride carbonbattery, and studied the influence of different storage time and different storagetemperature to the battery properties.At first, this paper assembled lithium fluorinated carbon batteries usingfluorinated carbon as cathode and lithium as anode, and studied the changes of batteryperformances when the lithium fluorinated carbon batteries were stored at40℃，55℃，70℃, then characterized the cathode surface morphology and the changes of thematerial phase before and after storage through SEM and XRD tests. The resultsshowed that the higher the temperature was, the longer time it stored, the capacitydecrease was more serious, the lower the voltage platform was and the more obviousthe voltage delay was. The SEM results showed that it produced manywell-distributed particles on the cathode of the battery, and the XRD results showedthat the self-discharge reaction occurred and it produced high resistance LiF when itstored at high temperature.Because of the activity of lithium, the battery capacity of thionyl chloride cellswould decrease when keeping at high temperature. The decay of capacities increasewith the time of storage, and the degree of attenuation is not the same after differenttime. This paper has studied the performance of lithium/thionyl chloride batteries afterhigh temperature storage. The results showed that the decay of both capacity and discharge platform is improved with increasing for both temperature and time ofstorage. However, the impedance of cells increases with the increasing for bothtemperature and time of storage. Furthermore, the open-circuit voltage of cellsincreases with the time of storage.Finally, this paper predicted the storage life of room temperature through theaccelerated life test. The storage life model obtained from0.01C discharge data was: t=0.00135+4900.45*0.9094T, and then obtained the result that the storage life ofroom temperature was456.19days. Similarly, The storage life model obtained from0.03C discharge data was: t=-0.8582+3362.6*0.91734T, and then obtained the resultthat the storage life of room temperature was388.09days.